1. Field of the Invention
This invention relates to gun propellants. More particularly, this invention relates to a method for improving the efficiency of and lowering the peak pressure produced by high force, high flame temperature gun propellants.
2. Description of the Prior Art
The military services utilize two types of gun propellants. One type is made up of extruded cylinders having one or more perforations. The other is called ball powder and is made up of spherical shaped particles, the outer portions of which contain an inert plasticizer such as dibutyl phthalate. The dibutyl phthalate is for the purpose of deterring the initial phase of burning.
Commonly, the extruded propellant is either a double base propellant made up of nitrocellulose and a second ingredient such as nitroglycerine, trimethylol trinitrate or the like or a single base propellant made up of nitrocellulose alone. These propellants produce a mass impetus of 340,000 or greater and a high flame temperature on the order of 3000.degree. K. or more when they are burned. When these propellants are burned, pressure in the gun chamber builds up quickly to a high peak and then rapidly decays. This requires the use of a heavy (thick) chamber in order to insure against rupture due to the high peak pressure. These propellants are consumed before the projectile has travelled more than a fraction of the length of the barrel. This process has an inherently low efficiency so that large amounts of propellant are required, an effect which tends to cause erosion of the throat area of the chamber.